PSY 250 Lecture Notes - Lecture 2: Axon Hillock, Myelin, Patellar Reflex

• School: Stony Brook University
• Department: Psychology
• Course: PSY 250
• Professor: Hoi- Chung Leung

Document Summary

Psy 250 biopsych | class notes 2. Signal needs to be generated, travel down length of axon and cross gap b/w neurons. 2 forms signal transmission: electrical & chemical. 4 main parts: soma, dendrites, axon hillock sums up pos and neg signals and if it"s enough pos activates the ap (action potential, axon, axon terminals/terminal buttons. Nodes of ranvier gaps in myelin sheath. Ions electrically charged molecules: sodium = na, potassium = k, chloride = cl, organic ions = a- Pos charged ions push other pos away, pos and neg attract. Cell membrane = phospholipid bilayer that separates intracellular and extracellular contnts: semipermeable. Ion channes/gates embedded proteins in cell membrane: specialize pores provide routes for ions to cross cell membrane. Allow specific ions to move across membrane but not others: vary in size, number distrubtion, 2 types: voltage-gated, ligand gated. Voltage gated specific to certain voltage/electrical current.